in this paper, we report on a compact prototype capable both of lensfree imaging, raman spectrometry and scattering microscopy from bacteria samples. this instrument allows high-throughput real-time characterization without the need of markers, making it potentially suitable to field label-free biomedical and environmental applications.
recent challenging tasks in many fields are the identification, analysis and characterization of single bacteria within heterogeneous mixture. raman spectroscopy and elastic scattering spectroscopy have shown success in application to biological problems. however, raman technique requires a careful positioning of the excitation source onto single bacteria dispersed in a liquid mixture and dried on a hard surface, such as microscope coverslip1-3. a new lensfree imaging technique that can serve numerous biological applications has been developed in the recent years4,5. with this technology we are able first to localize bacteria over a large fov, then to address investigation exactly over single microorganism pre-identified in order to follow with raman spectroscopy and diffracted pattern imaging6.